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Патент USA US2408759

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‘ Oct. 8, 1946.
’
' J_ DUNLQP
2,408,758
SAFETY APPARATUS ‘FOR ELEVATORS
Filed Oct. 29, 1943
2 Sheets-Sheet l
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AZORNEY
Oct. ,8, 1946. '
' J. DUNLQP
2,408,758
SAFETY APPARATUS FOR ELEVATORS
Filed 001:. 29‘, 1943
2 Sheets-Sheet 2
35
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WITNESSES:
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ATTORNEY
Patented Oct. 8, 1946
2,408,758
UNITED'STATES PATENT OFFICE
2,408,758
SAFETY APPARATUS FOR ELEVATORS
James Dunlop, Ridgewood, N. J., assignor, by
mesne assignments, to Westinghouse Electric
Corporation, East Pittsburgh, Pa, a corpora
tion of Pennsylvania
Application October 29, 1943, Serial No. 508,191
7 Claims.
(Cl. 18'7—-29)
I
2
My invention relates to safety apparatus for
hydraulically operated elevators and, more par
ticularly, to safety apparatus for elevators of the
deck-edge type in which the elevator platform is
raised and lowered by a plurality of cables oper
ated by a hydraulic engine.
One object of my invention is to provide for
stopping the operation of the elevator engine
therein to the main deck and is movable up and
down on the side of the ship to serve its main deck
and its flight deck. The elevator is very large
and the weights carried by the hoisting cables are
correspondingly heavy. However, it is to be un
derstood that the invention may be employed
with elevators used for other purposes.
Referring more particularly to Figs. 1 and 2,
I have illustrated a deck-edge elevator compris
ing an elevator platform 10 disposed between a
when any one of its hoisting cables becomes loose
or broken.
Another object is to provide a safety apparatus
responsive to the slackening or breaking of any
pair of guide rails l I and I2 mounted on the outer ‘
side of a ship hull l3 by a plurality of brackets
E4. The platform is supported by and is raised
and lowered between the main deck l5 and the
one of the hoisting vcables on an elevator for
stopping the elevator engine, which shall be posi
tive in operation, and simple and inexpensive
to manufacture, install, and maintain in operable
condition.
' ?ight deck "5 by a plurality of hoisting cables
For a better understanding of my invention,
reference may be had to the accompanying draw
I‘! and I8 operated by a hydraulic hoisting en
glue [9. A plurality of rollers 2| are mounted on
the ends of the platform in position to engage
a pair of vertical slots 22 in the sides of the guide
ings, in which:
rails facing each other, for guiding the platform
Figure 1 is a diagrammatic representation in
end elevation of a deck-edge elevator for ships
in which the elevator is supported and moved by
a plurality of hoisting cables operated by a
as it is raised or lowered.
hydraulic engine embodying my invention;
Fig. 2 is a diagrammatic representation from
the interior of a ship of the deck-edge elevator
shown in Fig. 1 and its power system;
Fig. 3 is an enlarged representation of the
power system for the elevator embodying my 30
The platform l9 comprises a base-section 23
and a hinged or outboard section 24 which nor
mally lie in the same plane and provide a large
level area upon which airplanes may be moved
from either deck to the other. The base 23 is
constructed with a suitable floor 25 mounted on
a frame of high tensile steel tubing 26 welded
together in bridgelike construction to form a rela
improved safety apparatus;
tively light but strong body or frame. The out
board section is constructed with a ?oor 21 and
Fig. 4 is a top plan view of the mechanical
parts of the apparatus applied to the hitches on
a frame 28 in a similar manner and is mounted
upon and connected to the base 23 by a suitable
hinge joint 29 so that it may be raised from its
Fig. 5 is a top plan view of only the safety 35 horizontal position into a vertical position on the
apparatus included in Fig. 4;
base to permit the ship to pass through a lock
Fig. 6 is a view in side elevation of the mechani
or other narrow opening.
cal parts of my safety apparatus applied to the
The hoisting engine [9 is a hydraulic engine
cable hitches of the elevator, some parts of the
comprising a single cylinder 34 mounted in a
walls of the hitch boxes being broken away to 40 horizontal position‘ on a frame or engine bed
disclose the safety parts more clearly;
35 and a power plunger 35 disposed in the cylin
Fig. 7 is a view in side elevation of only the
der. The outer end of‘the plunger is provided
mechanical parts of the safety apparatus shown
with a power head 31 inv which a pair of power
in Fig. 6;
sheaves 38 are rotatably mounted. The plunger
46
8 is a view in front'end elevation of the
in the cylinder moves back and forth horizontally
safety parts as applied to the cable hitches of the
and thus moves the power sheaves back and forth
the hoisting cables;
elevator; and
Fig. 9 is a view in end elevation of only the
safety parts illustrated in Fig. 8.
with it.
1
The plunger is designed for operation by a suit
able hydraulic medium such as oil placed under
My invention is illustrated in connection with a 50 pressure by any suitable equipment such as a
deck-edge elevator, such as is used on airplane
pressure tank 40, an exhaust tank 4| and a pres
carriers, ships for transferring airplanes from one
sure pump 42. A pump motor 43 is provided for
deck to another. The elevator is operated by
driving the pressure pump 42. The pressure sys
hoisting cables and is mounted on the outer side
tem is connected to the cylinder through a pair
of the ship in alignment with a door opening 65 of pipes 44 and 45 controlled by a suitable valve
2,408,758
3
4
45 mounted on the engine cylinder and connected
for operation by a valve motor 41. rI‘he valve 46
may be of any suitable type which shuts off and
stops the ?ow of oil into the cylinder when the
motor 4'! is stopped. The stopping of the ?ow
of oil into the cylinder stops the movement of
the bottom part of the rear end of the engine.
The nuts ‘Iii provide a means by which, in connec
tion with any well known cable tension tester,
the effective length of the cables may be so ad
J'usted that the tension of each one will equal
that of each other.
In order to avoid any serious accident result
the plunger and the movement of the elevator, as
the plunger remains stationary as long as no oil
ing from the failure of any one or more of the
cables by reason of breaking or loosening I have
enters or leaves the cylinder. The pump motor
43 and the valve motor may be connected to any 10 provided a safety device comprising a means for
stopping the engine and the platform such as a
suitable source of electrical energy by supply
safety switch ‘I4 for operating a relay ‘I5 to open
conductors such as L+ and L- controlled by
a pair of line switches 5I.
the circuits for the valve motor and the pump
The motor 43 is provided with a controller 43C
motor when a cable breaks or loosens; a span
connected to and responsive to a suitable pres
ning lever ‘It for operating the switch, a plural
sure device 5| in the upper part of the pressure
ity of trip rods ‘I1, ‘I8, "I9 and 80 for operating
the spanning levers and a- plurality of energy
tank 40 to provide a means for controlling the
operation of the motor in accordance with the
storing devices such as coiled springs SI, 82, 83,
M, 85, 85, 81 and SB and ‘actuators or spring
pressure in the tank so that the motor will start
the pump when the pressure falls below a prede 20 washers 90, 9|, 92, 93, 94, 95, 96 and 91 mounted
on the hitch rods for operating the trip rods.
termined value and will stop the pump when the
pressure reaches a predetermined value.
The washer 9D is provided with a collar or body
98 so that it constitutes a half spool like device
A controller ‘TC is disposed in the circuit of
and it is mounted concentrically on the rod be
the valve motor 41 to be connected to any suit
tween the nuts ‘ID and the wall 61. Thespring
able control operating means (not shown) where
8| is concentrically mounted on the body 98 of
by the valve motor may be controlled to operate
‘the washer and is held between the washer 90
the valve 46 to raise or lower the elevator.
and the wall 61 so that the nuts ‘Ill may be tight
A pair of down stopping blocks 48 are mounted
ened against the tension of the cable 62a until
on the cylinder block in position to limit the
they hold the washer body tightly against the
rearward movement of the plunger and a pair of
body 61 and thus compress the spring BI into
up stopping blocks 49 are mounted on a projec
the space between the washer and the wall. In
tion 50 seated on the engine bed in position to
asmuch as the washer and its body and the nuts
limit the forward movement of the plunger when
are solidly against the wall, they provide a dead
the platform is being raised to the ?ight deck.
end hitch for the cable. The uncompressed
The hoisting cables H at the lefthand of the
length and strength of the spring and the length
platform are secured to the base 23 by suitable
of the washer body are so selected that the nor~
hitches 52 mounted thereon and pass upwardly
mal tension of the cable will not be overcome by
and over an idler sheave 53 fastened to the ship
structure underneath the overhanging portion of
the spring and it will thus store energy to move
the hitch rod outwardly upon failure of the cable
the ?ight deck, thence rearwardly over a second
but it will not move the rod outwardly as long
idler sheave 54 mounted on the ship frame inside
as the cable maintains its normal tension. The
the hull, thence downwardly and under a de?ec
other springs and washers are mounted on the
tor sheave 55 mounted on the engine bed 35,
other cable rods in the same manner.
thence around a stationary sheave 56 mounted
The trip rods TI and ‘I8 are connected at their
on the engine bed, thence around one of the
bases by a yoke I00 so that they form an integral
power sheaves 38 and thence to a plurality of
hitches 51 mounted on the lower part of the rear
structure, and the bases of the trip rods ‘I9 and 80
end of the engine.
are connected by a yoke I'DI which in turn is con
The hoisting cables II! at the righthand end
nected to a shaft I02 so that they constitute an
integral structure. The trip rods 11 and ‘I8 are
of the platform are secured to the base 20 by
bracket 58 mounted thereon and pass upwardly
provided with notched or shouldered portions I03,
‘ I04 and I05 and are slidably disposed in the walls
and over an idler sheave 59 fastened to the ship
61 and 68 of the hitch box 69 in position approxi
structure underneath the overhanging portion of
mately parallel to the hitch rods 65 with the
the ?ight deck, thence rearwardly over a second
idler sheave 60 mounted on the ship frame inside
washer 90 in the notch I03 and the washer GI in
the hull and thence downwardly and under a de
the notch I34 and the washers 92 and 93 in the
notch I55. The trip rods ‘I9 and 80 are pro
?ector sheave 6| mounted on the engine bed and
thence under and over one of the power sheaves
vided with notched or shouldered portions I06,
I 01 and H38 and are slidably disposed in the walls
38 mounted in the plunger head and thence to
TI and T2 of the hitch box ‘I3 in position approxi
dead end hitches 62 mounted on the upper part
of the rear end of the engine.
mately parallel with the rods 51 and with the
As illustrated in Fig. 4, the upper cable ‘hitch
washer 94 in the notch I 05, the washer 95 in the
62a comprises a socket 84 mounted on the end of
notch I 01 and the washers 95 and 91 in the notch
the cable, a rod 65 secured in the outer end of
I08.
the socket by a pivot pin 66 with the outer end
The trip rods are held with their shoulders
of the cable rod extending through the walls 61
formed by the notches against the outer faces of
and 68 of a hitch box 69 mounted on the top part
the washers and the length of each notch is suffi
cient to permit the trip rods to move outwardly
of the rear end of the engine, and a pair of nuts
‘I0 disposed on the rod beyond the wall 61 by
under the action of any one or more of the wash~
ers suf?ciently to operate the safety apparatus
means of which the eil’ective length of the cable
without touching the rear faces of any of the
may be adjusted. Each of the cable hitches 62
other washers. With this arrangement of the
is constructed and mounted in the same manner.
trip rods and washers, the breaking or dangerous
The cable hitches 51 are also constructed in the
loosening of any one of the cables will permit its
same manner with their rods extending through
rod to move outwardly under the energy stored
the walls ‘II and ‘I2 of a hitch box ‘I3 mounted on
2,408,758
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in the compression spring thereon and thus cause
its spring washer to engage the shoulder portion
of the trip rod With which it is associated and
to escape to effect this result. The escape of the
oil from the cylinder permits the plunger to move
move it outwardly, without affecting any other
cable hitch.
The ‘spanning lever is mounted with its forked
upper end I09 resting in the bottom of the notch
I05 of the trip rod ‘I8 and its lower end H0 rest
weight of the platform; As the plunger nears the
end of its rearward stroke, the valve 46 is oper
gine cylinder. The compression spring H2 lies
It will be assumed now that while the elevator
is being raised from the lower deck to the upper
deck the cable 02a breaks or becomes loosened
to such an extent that it becomes dangerous and
thereby permits thé energy stored in the spring
8| to move the washer. 90 and the hitch rod 05
rearwardly under the pressure exerted by the
ated to its closed position and the plunger reaches
the down stopping blocks 48 and is stopped to hold
the platform at the main deck.- The down stop
ing on a pin III in the outer end of the shaft
ping blocks and the lengths of the cables are so
I02 and it is maintained in this position by a 10 adjusted that the platform is in position to serve
biasing compression spring H2 mounted by a
the main deck when the plunger‘ is stopped :by its
stud bolt H3 disposed in the rear end of the en
down stopping blocks.
between the nut on the stud bolt and the outer
face of the spanning lever so that it presses or
biases the lever toward the rear end‘ of the en
gine cylinder and causes its ends I09 and H0
to press the trip rods to the left to maintain them
in their normal position against the spring wash
outwardly, thus moving the washer 90 against
ers 90, 9I, etc.
20 the notched portion I03 of‘the trip rod 11. The
Inasmuch as the yoke I00 connects the trip rods
pressure of the washer 90 against the trip rod
‘H and ‘I8, the outward movement of either rod
11 moves it outwardly and with it the yoke I00
will move both of them outwardly so that the rod
and the trip rod ‘I8. The outward movement of
18 presses against the upper end I09 of the span
the trip rod ‘I8 forces the upper end I09 of the
ning lever and moves it outwardly. Also, inas
spanning lever outwardly by reason of the posi
much as the yoke I0! connects the rods ‘I9 and
80 and the shaft I02, the outward movement of
either trip rod ‘I9 or 80 will move both of them
and the shaft I02 outwardly against the lower
end IIO of the spanning lever and thus move
it outwardly.
The switch ‘I4 is mounted on a bar I I6 welded
or otherwise secured to the engine bed 35 and
is provided with a switch arm H? on the outer
end of which is disposed a roller H8 in position
tion of its lower end H0 on the shaft I02 and
thereby pushes the switch arm I I1 outwardly until
it opens the switch ‘I4 thereby deenergizing the
relay ‘I5. The deenergized relay 15 opens its con
tacts 15b and its contacts 150 thus deenergizing
the valve motor 41 and pump motor #3 to imme
diately stop all operations of the hoisting system.
ning lever ‘I0 moves the switch arm to open
If any two of the cables break simultaneously,
for instance, those attached to the hitch rods ‘I20
and 12d (Fig. 4), the washers 96 and 91 disposed
in the notch 508 of trip rod ‘I9 and against the
righthand shoulder formed by that notch will
force the rod outwardly and the rod will force
the lower end of the spanning lever outwardly.
The outward movement of the lower end of the
spanning lever will pivot the lever on its upper
end in the notch I05 of the trip rod 18 and thus
open the switch ‘I4 by moving the switch arm I I1
outwardly. The opening of the switch ‘I4 will
deenergize the switch ‘I5 and thereby open the
circuits for the valve motor and pump motor
to shut down the hoisting system of the eleva
switch position. The relay ‘I5 is provided with
tor.
to rest against the outer central portion of the
spanning lever ‘l5 so that any outward move
ment of the spanning lever will move the switch
arm I II to open switch position.
The relay ‘I5 may be mounted in any suitable
position with the one lead to its coil 15a con
nected to the supply conductor L- and its other
lead extending through the switch ‘I4 to the sup
ply conductor L+ so that the relay will remain
energized as long as the switch ‘I4 is in its closed
position but will ‘be deenergized when the span
‘
contacts 15b to close the circuit to the valve mo
By reason of the foregoing description, it will
tor 41 and with contacts ‘I50 to close the circuit 50 be seen that I have provided a reliable and safe
to the pump motor 43 to cause these circuits to
system which will stop any further operation of
remain in operative condition as long as the re
the elevator as ‘soon as any one or any number
lay remains energized but to open these circuits
of the hoisting cables break or loosen to a dan
for the purpose of stopping the valve motor and
gerous degree. It will also be evident that the
55 apparatus is sturdy and so simple in nature that
the pump when the relay is deenergized.
In an assumed operation of the elevator, with
it cannot easily get out of order and that it will
the platform at the lower deck, the valve 46 on
operate effectively regardless of only one cable
the engine 19 is operated to admit oil under pres
breaking or half a dozen cables breaking simul
sure to the cylinder. As the oil ?ows into the
taneously. It will also be apparent that the ap~
cylinder, it forces the plunger forward and there
paratus may be inspected easily and that it will
by moves the power sheaves 38 to the left. As
be inexpensive to maintain in operation.
the power sheaves move toward the left, they exert
Although I have illustrated and described only
a pull on the hoisting cables I1 and I8 and thus
one speci?c embodiment of my invention, it is to
cause them to raise the platform I0 until it is
be understood that changes therein and modi?
65 cations thereof may be made without departing
even with the ?ight deck.
As the platform approaches the ?ight deck, the
from the spirit and scope of the invention.
valve 46 is operated to decrease the amount of
I claim as 'my invention:
oil being admitted to the engine cylinder 36 to
1. In an elevator, a plotform for serving a lower
zero, and the pressure of the oil in the cylinder
floor and an upper floor, a plurality of hoisting
now maintains the plunger against the cables with 70 cables for raising and lowering the platform, an
su?icient force to hold the platform in its upper
engine for operating the hoisting cables, a hitch
position.
box, a hitch rod connected to each cable and
It is assumed now that the platform is to be
slidably mounted in the hitch box, an energy stor
lowered to the main deck and that the valve 45
ing device disposed on each hitch rod to store
is operated to permit the oil in the cylinder 36
energy when its cable is under tension for moving
2,408,758,
7
that hitch rod outwardly upon failure of its cable,
a plurality of trip rods slidably mounted approxi
mately parallel to the hitch rods in the hitch box,
a yoke connecting the trip rods into an integral
structure, an actuator mounted on each hitch
rod and responsive to outward movement of that
hitch rod for moving the trip rod structure out
wardlyv and means responsive to outward move
storing energy when the cable is under tension
to move that hitch rod outwardly upon failure of
its cable, a washer mounted on each hitch rod
between the spring and the nut thereon, the
periphery of said washer extending beyond the
sides of the spring, a collar for limiting the
compression of the spring, a plurality of trip rods
connected into an integral structure and slidably
disposed in the hitch box in approximately par
ment of the trip rod structure for stopping the
10 allel relation to the hitch rods and provided with
engine and the platform.
notches for receiving the edges of the spring
2. In an elevator, a platform for serving a lower
washers, whereby a predetermined outward
?oor and an upper ?oor, a plurality of hoisting
movement of a washer will move the trip rod
cables for raising and lowering the platform, an
structure outwardly, a switch connected in the
engine for operating the hoisting cables, a hitch
box, a hitch rod connected to each. cable and 15 control circuit for the motive means, a spanning
lever pivotally mounted on the engine with one
portion disposed in engagement with one of the
trip rods and another portion disposed in en
energy when its cable is under tension for mov
slidably mounted in the hitch _box, an energy stor
ing device disposed on each hitch rod to store
gagement with the switch whereby outward
ing that hitch rod outwardly upon failure of its
cable, a trip rod slidably disposed in the hitch 20 movement of the trip rod structure will cause
the lever to move the switch to open position
box and provided with shoulder portions, an actu
and thereby stop operation of the engine, and
ator mounted on each hitch rod and disposed
resilient means for biasing the spanning lever
against a shoulder portion of the trip rod whereby
against the trip rod structure.
a predetermined outward movement of any one or
6. In an elevator, a platform for serving an
more of the hitch rods will cause outward move~ 25
upper floor and a lower ?oor, a ?rst set of hoist
ment of the trip rod, and means responsive to
outward movement of the trip rod for stopping
the engine.
3. In an elevator, a platform for serving a lower
floor and an upper floor, a plurality of hoisting
cables for raising and lowering the platform, an
engine for operating the hoisting cable's, a hitch
rod connected to each cable and slidably mounted
on the engine, an energy storing device disposed
on each hitch rod for storing energy when its
cable is under tension to move that hitch rod out
wardly upon failure of its cable, a trip rod slid
ably disposed on the engine in approximately par
ing cables attached to one end of the platform,
a second set of hoisting cables attached to the
other end of the platform, a hydraulic engine
for operating the hoisting cables, a ?rst hitch
box for the ?rst set of cables, 21 second hitch box
for the second set of cables, a ?rst set of hitch
rods, one for each of the ?rst set of cables, slid
ably mounted in the ?rst hitch box for connect
ing the ?rst set of cables to that hitch box, a
second set of hitch rods, one for each of the
second set of cables, slidably mounted in the
second hitch box for connecting the second set
of cables to that bitch box, an energy storing
allel relation to the hitch rods, a connector
mounted on each hitch rod for engaging the trip 40 device on each hitch rod and responsive to the
tension in its cable for moving it outwardly upon
rod and moving it outwardly when that hitch rod
failure of that cable, a plurality of trip rods
is moved outwardly by failure of its cable, and
slidably disposed in each hitch box approximately
means responsive to an outward movement of the
parallel to the hitch rods therein, a yoke con
trip rod for stopping the engine.
4. In an elevator, a platform for serving a lower Li necting the trip rods in the ?rst hitch box into
an integral structure, a second yoke connecting
?oor and an upper floor, a plurality of hoisting
the trip rods in the second hitch box into an
cables for raising and lowering the platform. an
integral structure, a connector associated with
engine for operating the hoisting cables, a hitch
each hitch rod in the ?rst hitch box and the
rod connected to each cable and slidably mounted
trip rods therein for moving the trip rods in that
on the engine, a compression spring mounted on
box outwardly upon failure of any cable attached
each hitch rod between the end of the rod and
to a hitch rod in that box, a connector associ
the engine to store energy when the cable is under
ated with each hitch rod in the second hitch box
tension for moving that hitch rod outwardly upon
and the trip rods therein for movingr them out‘
failure of its cable, a washer mounted on each
hitch rod between the spring and the end of the ‘ wardly upon failure of any cable attached to a
rod, a trip rod slidably disposed on the engine in
hitch rod in that hitch box, a spanning lever
pivotally mounted on the engine with its one end
approximately parallel relation to the hitch rods
and provided with notches for receiving the edges
connected with one of the trip rods in the first
hitch box and its other end connected with one
of the washers, a spanning lever pivotally mount~
ed on the engine in position to be moved out
of the trip rods in the second hitch box, means
for biasing the spanning lever against the trip
wardly by a predetermined outward movement of
the trip rod, and means responsive to a predeter~
rods, and a switch responsive to operation of the
lever by the trip rods in either hitch box for
mined outward movement of the spanning lever
for stopping operation of the elevator platform.
stopping the operation of the engine upon failure
5. In an elevator ,a platform for serving a
lower floor and an upper floor, a plurality of
hoisting cables for raising and lowering the
‘ platform, an engine for operating the hoisting
cables, control means for the engine, a hitch.
box associated with the engine, a hitch rod con~
nected to each cable and slid-ably mounted in
the hitch box, a nut on the outer end of each
hitch rod for adjusting the effective length of its
cable, a compression spring disposed on each
hitch rod between its nut and the hitch box for
’ of any one of the hoisting cables.
'7. In an elevator system, a platform for serving
an upper floor and a lower floor, a ?rst set of
cables for one end of the platform. a second set
of cables for the other end of the platform, an
engine for operating the cables, a first hitch box
for the ?rst set of cables, a second hitch box for
the second set of cables, a plurality of hitch rods,
one for each of the ?rst set of cables, slidably
mounted in the first hitch box, a second set of
75 hitch rods, one for each of the second set of
2,408,758
9
10
cables, slidably mounted in the second hitch box,
box into an integral structure, a shaft mounted
on the outer end of the second yoke and disposed
a compression spring disposed on each hitch rod
approximately parallel to the trip rods attached
and responsive to the tension of the cable at
to the yoke, a spanning lever pivotally mounted
tached thereto for moving that hitch rod out
with its one end in pivotal contact with one of
wardly upon failure of that cable, an actuator
the trip rods in the ?rst hitch box and its other
mounted on each hitch rod, a plurality of trip
end in contact with the shaft attached to the
rods slidably disposed in each hitch box and
trip rods in the second hitch box, resilient means
provided with notches intermediate their ends
for biasing the spanning lever against the trip
disposed to receive the ends of the actuators on
the hitch rods associated therewith so that the 10 rods, and means responsive to operation of the
lever by either one of the trip rod structures for
outward movement of any hitch rod will move the
stopping the operation of the engine upon failure
trip rod associated with it outwardly, a yoke
of any one of the hoisting cables.
connecting the trip rods in the ?rst hitch box
to form an integral structure, a second yoke
JAMES DUNLOP.
connecting the trip rods in the second hitch 15
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